Electronic devices, such as tablets, computers, copiers, digital cameras, smart phones, control systems and automated teller machines, among others, often employ electronic components which leverage chip package assembly for increased functionality and higher component density. Conventional chip packaging schemes often utilize package substrates, often in conjunction with a through-silicon-via (TSV) interposer, to enable a plurality of integrated circuit (IC) dies to be mounted to a single substrate. The IC dies may include memory, logic or other IC device.
In many instances, a lid is utilized to substantially cover one or more of the dies. The lid is part of the packaging of the IC structure. The lid can be formed of a plastic, metal or other suitable material, and is mounted to the die and interposer or package substrate using an adhesive, such as a heat transfer paste or other suitable bonding material. The lid functions to protect the die from damage, such as from impact from another object or from ultraviolet light which might damage the die.
The lid is often heated during installation over the die. Once the lid cools to room temperature, the lid may deform in a concave manner such that the center region of the lid becomes closest to the die. Once heated while in operation, the lid may straighten out and become more planar. The straightening of the lid in certain instances may cause the lid to become delaminated from the die. Once delaminated, the lid may become detached from the IC packaging. Additionally, the delamination of the lid from the die changes the rate of heat transfer between the die and lid, which may detrimentally effect device performance and reliability.
Therefore, a need exists for an improved chip package assembly, and in particular, to chip package assemblies having improved lid to integrated circuit (IC) die adhesion.